My Google Maps is in English, and when I want to a share a location it gives me the address in English.
But how can I get this address string in another language? I can't find a way to translate it.
If there is no language exists for the address except the English language, then there is no translation of the address. You get only the address in English language.
Some addresses were filled up by the native language of that address only if Google map interface was in that language and the address was edited by a native speaker of that language. For example, if you search for The Great Pyramid of Giza in Egypt, you will find that the address was written in both English and Arabic:
But if you click on the suggest an edit at the bottom of the screenshot above, you can only edit the English language, and it will not allow you to access the Arabic address:
But if you change the interface of Google Maps to Arabic, you can access the address in Arabic language:
The conclusion is unless someone fill up the non-English address information in that certain language, you will not get the address translated automatically.